Annotate Muscle Z-Score Function

Hi everyone, I also have a question about the annotate_muscle_zscore function.

The EEG recordings I am working with were sampled at 200 Hz, which means the Nyquist frequency is 100 Hz. I am aware that the default frequency range of the annotate_muscle_zscore function is 110-140 Hz, which is higher than the Nyquist frequency for these EEG recordings.

Is there a lower frequency range that I could specify? If there is, which frequency range would you recommend?


  • MNE version: 1.0.3
  • operating system: Windows 11

Thank you for your help!

if your sampling frequency is only 200 Hz then you probably won’t / can’t see any muscle artifacts. Why do you want to use that function? Are you seeing artifacts anyway (are you sure they’re from muscle activity)?

Hi Dan, I would like to use that function to remove muscle artifacts that have frequencies below the Nyquist frequency (100 Hz, in our case). I have seen muscle artifacts within this range, and I am sure that they are from muscle activity. I have also looked into previous literature, which explains that the power-frequency spectrum of muscle artifacts is from 2-100 Hz, which is another reason why I believe muscle artifacts could exist within this range.

in that case, there should be no problem with using lower frequency parameters in the function.

(sorry if I came across as overly skeptical before; I’m not an expert in muscle artifacts, was just trying to get the full picture of what you’re trying to do, to make sure that annotate_muscle_zscore is indeed the right tool.)

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@lmctx13 The documentation for annotate_muscle() actually references the following publication (a review), which lists which frequency ranges have been reported (and in which recording sites):

That sounds good! It’s all right. I understand that you were getting the full picture, and I appreciate your help.

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I can look at this. Thank you!

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